Rotating Shaft
This boundary feature specifies flow conditions on boundaries where the fluid is subjected to a solid shaft rotation. This feature can be applied to rotating shaft boundaries in a free-surface domain modeled by a Deforming Domain that connects to a rotating shaft in a Rotating Domain.
The flow condition prescribed by the feature corresponds to a rotational velocity defined from an existing Rotating Domain. In order for the contact line, defined by intersection of the rotating shaft and the free surface, to be able to move along the rotating shaft the velocity condition is applied using a Wall boundary condition with the Navier Slip option for laminar flow. For turbulent flow, wall functions or automatic wall treatment must be applied.
Rotating Shaft
Axis of Rotation
Select the Axis of rotation. If x-axis is selected, this corresponds to a rotational axis (1, 0, 0) with the origin as the base point. Correspondingly, if y-axis or z-axis is selected, the rotational axis is defined by a unit vector in the selected direction together with a base point at the origin. For User defined enter values into the fields Rotation axis base point and Rotation axis direction. The z-axis is the default choice and the default values in the fields for User defined correspond to those for the z-axis.
Angular Velocity
Select the rotating shaft Rotational frequency from the list:
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Select the Revolution per time option to manually define the rotational velocity (SI unit: rad/s) and select the Rotational direction as Positive angular velocity or Negative angular velocity. This is the default setting.
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Select the Angular velocity option to manually define the angular velocity (SI unit: rad/s).